code: def load_baseline(
      baseline_path: Path, ref: str = "HEAD"
  ) -> str | None:
      status, out, _ = git("show", f"{ref}:./{baseline_path!s}")
      return out if status == 0 else None
  
file_path: bokeh/tests/test_cross.py
imports: from __future__ import annotations
  import pytest
  import os
  import signal
  import subprocess
  import sys
  import time
  from pathlib import Path
  from typing import TYPE_CHECKING, Literal, NoReturn, Union
  import _pytest.config
  import _pytest.mark
  import _pytest.python
label_desc: Use image node_id 5 for calling a global function with example usage: load_baseline(baseline_path, ref) and returns: unknown